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Calculate the pounds of gasoline per unit time, that the pump can deliver and the horsepower the pump can support, using these metrics;

Take the given pump's rated fuel flow in LPH, convert it to gal/hr (1 Gal = 3.785L), then convert the GPH figure to lbs/hr. Gasoline with a 10% ethanol content, which is just about everywhere, has a SPGR is 0.755. Calculate the weight of gas per minute the pump can pump. Just because a pump is rated at X LPH does not mean it will pump X LPH of fuel per minute. See the TI-Automotive chart below for their 405LPH F90000262 pump;
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When pumping against a head, an electric fuel pump's rated capacity is reduced. Check the chart above (again) for the F90000262 TI-Auto fuel pump. It can have a flow rate anywhere from 440lph to zero lph, depending on the head it is pumping against and the voltage and current it is being driven by. Ford uses a factory base fuel pressure of 39.15 psi for Terminator engines. Other engines may move this figure around.

When you add boost, it is additive to the required fuel system pressure and will raise the 39.15 psi number in operation under boost. At a 39.15 PSI base fuel system pressure, add an additional 20 psi of fuel pressure if your blower adds 20 psi of boost. That means your fuel pump will be pumping against 39.15 psi + 20 psi and requires 59 psi in the fuel system.

At a 60 psi operating pressure and 13.5 volts, the 405 LPH Ti-Auto pump can only produce 346 LPH of fuel. If your electrical system can only muster a continuous 12 volts to the fuel pump, then that figure drops to 287 LPH. If you supply less than 12 volts to the pump, then you are getting onto progressively thinner and thinner piston-burning ice.

In round numbers, it takes 10 lbs of air per minute to produce 100 HP. If you use an 11.08 AFR for max power with E-10, that means you take a given pump's fuel flow in LPH, convert it to gal/hr (1 Gal = 3.785 L), then convert the GPH figure to lbs/hr. Gasoline, with a 10% ethanol content, which is just about everywhere, has an SPGR is 0.755. The TI-Automotive pump that pumps at 440 lph is capable of supporting 116 GPH pumping against a zero head at 13.5 volts.

To provide for good air days, you should not look to use more than 80% or so of your pump's maximum delivery capability. 80% of 116 gph is 92 GPH. 92 GPH is 578 lbs per hour or 9.633 lbs per minute. At an 11.08 AFR, that would require 107 lbs of air to burn the fuel. Using the 10 lbs of air per minute for 100 HP metric means that the pump could support 1070 HP with a zero pressure head and a 13.2-volt continuous power supply, but of course, that is not the real world — at least not your real world

TI publishes its pump data on its website. Go to the website and download the relevant data for the pump you are interested in. Very important, before you go there, determine how much fuel your engine will require for the target power level you are shooting for. Additionally, take the measurements to determine the voltage at the pumps while the engine is under power. Find the fuel pump on their site that meets your flow volume requirements with a minimum of 20% headroom, and at the voltage your electrical system is capable of providing.
 

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Holy shity guy... I read this a few times and still do not understand 🙃 I appreciate the information, but I'm not sure how to apply it to my application 😅

You want to personally get more familiar with the theory and operation of EFI systems or buy that expertise from a shop.
 

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I have a 340amp alternator, 8gauge wire upgrade, 8an feed fuel line,525 hellcat pump with a jms bap... I'm shooting for as much hp as possible...
An 8 gauge wire for a 340 amp alternator is seriously undersized. You should be using one of the Alternator Reseller's 4 gauge (or larger) wire upgrades..
 
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